Atomic Theory Quiz

John Dalton

came up with the modern atomic theory: small particles, indivisible, identical properties, form compounds, can be rearranged, 1803, conservation of mass

what device allowed atoms to be seen

Scanning Tunneling Miscroscope (STM)

Cathode ray

streams of particles carry a negative charge. proved electrons exist

oil drop experiment

proved electric charge is a fixed amount. oil drop is balanced with gravity and charge and suspended in the middle. robert millikan

unit for charge

coolomb

JJ Thomson

discovered the electron by cathode ray in 1897

E. Rutherford

discovered the nucleus (protons), gold foil experiment with alpha rays and some of them deflected to indicate positive charge within the nucleus . 1911

democritus

came up with the idea of atoms in 400 BC and called them invisible and tiny particles. observed the world around him. “atomos”

Niels Bohr

discovered how electrons behaved, heated hydrogen gas only emits light at specific wavelengths, 1913

quantum mechanical model

aka electron cloud mode, made by erwin Schrodinger in 1926

Nuclear fission

nucleus of a heavy atom splits into two or more smaller nuclei, releasing a tremendous amount of energy

James Chadwick

discovered neutrons by bombarding beryllium and discovering that they emitted neutral partical called neutrons

extensive

depends on measuremetn

intensive

doesnt depend on measurement